Method of promoting carbonization in the door region of a coke oven and oven door therefor

ABSTRACT

A gas passage is formed on the inner surface of an oven door of a coke oven. Combustible gas which is generated during carbonization of coal in the coke oven is introduced into the passage, an oxygen-containing gas is introduced into the gas passage from a nozzle installed on the sole plate of the door region, ingress of charged coal into the gas passage is prevented, the combustible gas is combusted in the gas passage, a decrease in temperature in the door region common in the prior art is made up for, and the carbonization of coal is thereby promoted.

TECHNICAL FIELD

This invention relates to a method for promoting carbonization in a doorregion and to the structure of an oven door which overcomes nonuniformcarbonization during manufacture of coke in a chamber oven.

BACKGROUND OF THE INVENTION

As is well known, a method for manufacturing coke using a chamber ovenis a method in which a carbonizing chamber is charged with coal and isheated by heat coming from combustion chambers on both of its sidesthrough brick walls. It is known that coke which is manufactured by thismethod varies greatly in quality in the length, height, and widthdirections of the carbonizing chamber. Recently, increasing theeffectiveness of carbonization in a coke oven and stabilizing thequality of coke have come to be considered very important, and improvingthe quality within carbonizing chambers and improving the carbonizingtemperature have become important topics. In particular, as for thevariation in quality of coke and variation in carbonization temperaturein the lengthwise direction of an oven, there is a marked degree ofvariation in these properties in the door regions at the pusher sidewhere coke is pushed and the coke side where coke is discharged, sounless an improvement in the nonuniform carbonization at these doorregions is devised, it can be said that efficient carbonization andstabilization of the quality of coke in a coke oven are impossible.

FIG. 1 is a partially cross-sectional schematic view of a chamber oven10. Normally, the carbonizing chamber 12 of a chamber oven 10 is formedfrom a space which is elongated in the horizontal direction having alength of 13-17 meters, a height of 4-7.5 meters, and a width of 0.4-0.5meters and having an oven door 18 installed on the door region 16 on therear side and the door region 16 on the front side. In order to make iteasier for an unillustrated pusher to push coke to the outside of theoven after the completion of carbonization, the door region on the cokeside has an increased width on the order of 50-80 mm.

As shown in the partially cross-sectional plan view in FIG. 2, an ovendoor 20 elongated in the vertical direction is installed on the doorregion 16. This oven door 20 is formed from a main metal frame 20a onthe exterior, interior metal frame 20b connected thereto, and a heatinsulating material 23 secured to the interior metal frame 20b. Whenevercoke is pushed through the chamber, the doors 20 in the rear and frontdoor regions 16 are removed and the door regions are exposed to theexternal air, and there is much heat dissipation. In addition, when cokeis being pushed, the oven door 20 contacts the outside air and iscooled, and there is also much heat dissipation to the outside air fromthe oven door 20 itself which is again installed after the completion ofcoke pushing. As a result, the temperature of the door region falls byalmost 100 degrees C. with respect to the average temperature of eachcombustion chamber.

For this reason, the charged coal in the vicinity of the oven ports iscoked more slowly than coal at the center of the oven, so nonuniformcarbonization is unavoidable.

As a means of solving the problems of nonuniform carbonization at thedoor regions, i.e., oven ports, countermeasures have been attempted suchas increasing the amount of fuel gas supplied to the region of thecombustion chamber adjoining the door regions compared to other portionsor increasing the calories of the fuel gas to increase the temperature.However, there is a limit to how much the temperature of the combustionchamber can be increased, and conditions have not yet reached the pointthat an adequate effect has been achieved.

A method has been proposed in which the water content of the coalcharged in the door regions is lowered with respect to the water contentof coal charged in the center (Japanese Published Unexamined PatentApplication No. Sho 60-32885). This method has been affirmed inprinciple, but a practical method has not been established for chargingcoal of different water contents into the door regions and the center ofa carbonizing chamber, so this method is not practical.

As shown in FIG. 3, as an active measure with respect to the oven door,an oven door has been proposed in which the main metal frame 32 of anoven door 30 is lined with an insulating material 33, a heat resistantplate 35 is installed thereon through connecting members 34, and a gasconduit 36 for promoting the discharge of coke oven gas which isgenerated during carbonization in the space between the insulatingmaterial 33 and the heat resistant plate 35 is provided in the verticaldirection. Air or oxygen is introduced through the gas conduit 36 via apipe 37, coke oven gas is combusted, and heat is actively increased. SeeJapanese Published Examined Patent Application No. Hei 5-38795(JapanesePublished Unexamined Patent Application No. Sho 63-112686).

SUMMARY OF THE INVENTION

As the heat resistant plate 35 of the oven door 30 disclosed in theabove-mentioned Japanese Published Examined Patent Application No. Hei5-38795, stainless steel is generally used for reasons of economy, butdue to problems such as heat deformation and corrosion, its durabilityis inadequate. A ceramic material which has durability has also beentried, but not only is it expensive, but it has poor impact resistance,so it cannot stand up to actual use. Furthermore, the connecting members34 are directly exposed to high temperature combustion gases which arecombusted by air or oxygen from the outside of the oven, so they aresubjected to thermal deformation or corrosion, and there is a problemwith respect to their durability. In addition, in order to avoid contacttrouble at the time of removal or installation of the oven door, aprescribed gap is left between the heat resistant plate 35 and the ovenwall 38, but as the heat resistant plate 35 is thin, a portion of thecharged coal can enter the gas conduit 36 from this space, turn to coke,and stick to the oven wall or other portion, so not only does it becomeimpossible to smoothly perform removal and attachment of the oven door,but a large portion falls and piles up in the door regions, and this maybe an impediment to discharge of coke. This tendency is particularlyprominent with respect to today's humidity controlled coal operations.

Moreover, with this oven door structure, coke oven gas which passesthrough the gas passage unavoidably directly contacts the metal doorframe, and a considerable portion of the heat which is generated by gascombustion within the gas passage is dissipated to the outside throughthe door frame. Thus such dissipated heat can not be effectively used inimproving carbonization in the door regions, and it leads to anincrease, through the door frame, in the temperature of a protectiveplate which is normally a cast metal, and due to expansion damage of theprotective plate, there is a great possibility of heavy damage to theoven body. For these reasons, this structure has not reached the pointof actual use.

The object of the present invention is to solve problems like thosedescribed above of conventional oven doors and to provide a method ofprompting carbonization in a coke oven door region which can effectivelyprevent the ingress of charged coal into a gas passage which is animpediment to oven operation and can do away with the delay in cokecarbonization in the above-described door regions.

The present inventors performed various experimental research for thepurpose of achieving the above-described object. As a result, they foundthat if a plurality of heat resistant members having a nearly concavecross section and sloping surfaces at their upper and lower ends arefitted to form a closed space with a space left between the neighboringheat resistant members, a gas passage can be formed in the main metalframe of an oven door through a heat insulating material, ingress ofcharged coal into the gas passage can be prevented and the flow of cokeoven gas from the carbonizing chamber to the gas passage can beguaranteed, stabilized combustion is possible by blowing air or oxygen,and the dissipation of heat to the door frame can be prevented, therebycompleting the present invention.

Namely, the present invention is a carbonizing promoting method for acoke oven door region and an oven door structure therefor, characterizedin that combustible gas which is generated during carbonizing of coal ina coke oven (hereunder also referred to simply as coke oven gas) and anoxygen-containing gas are introduced into a gas passage formed on theinner side of an oven door of a coke oven, the ingress of charged coalinto the gas passage is prevented, the combustible gas is combusted inthe gas passage, and the carbonizing of coal in the door regions ispromoted.

According to another aspect, the present invention is a carbonizingpromoting method for a coke oven door region and an oven door structuretherefor, characterized in that a plurality of heat resistant membershaving a nearly concave, i.e., channel-like, or cylindrical crosssection and sloping surfaces at their upper and lower ends are fitted toform a closed space with a space left between the neighboring heatresistant members, a gas passage is formed in the main metal frame of anoven door through a heat insulating material, and oxygen-containing gasis blown into the gas passage and coke oven gas is combusted.

According to yet another aspect, the present invention is a carbonizingpromoting method for a coke oven door region and an oven door structuretherefor, characterized in that a heat insulating material is providedon the inner side of main metal frame of an oven door of a coke oven,and then a vertically extending gas passage is formed using heatresistant members which have a cross section which is generallycylindrical or concave and which has a side portion thickness which isgreater than the front portion thickness, the joint with the insulatingmaterial is sealed so that charged coal can not enter the gas passage,an oxygen-containing gas is blown into the gas passage, and a portion ofthe coke oven gas which is generated during carbonizing is combusted.

According to a preferred mode of the present invention, a heatinsulating material is provided on the inner side of main metal frame ofan oven door of a coke oven, then a plurality of heat resistant memberscontaining reinforcing fibers and having a cross section which isgenerally cylindrical or concave and having a side portion which isthicker than the front portion and having an upper end surface whichslopes outward and a lower end surface which slopes inward arevertically aligned in series, the sloping surfaces of the upper andlower ends of the heat resistant members are made to face each otherwith a space in between and are secured to the main metal frame with aconnecting member through the heat insulating material to form a gaspassage extending vertically, the joints with the heat insulatingmaterial are sealed to prevent ingress of the charged coal into the gaspassage, an oxygen-containing gas is blown into the gas passage, and aportion of the coke oven gas which is generated during carbonizing ofthe charged coal is combusted.

Thus, it is extremely effective to introduce coke oven gas from theinside of the oven and an oxygen-containing gas from the outside of theoven into the gas passage formed on the inner side of the oven door, andthey are combusted in order to overcome nonuniform carbonizing in thedoor regions. However, in this method, the manner of blowing air oroxygen into the gas passage from the outside is extremely important.

Normally, when the coke is discharged, an oven door is removed from theoven. Accordingly, since piping is installed directly on the oven doorto blow an oxygen-containing gas it is necessary to remove and installthe piping each time the oven door is detached or attached. For thisreason, actual operation with such a structure is extremelytime-consuming, and when the operating time efficiency is high, there isthe possibility of the time required for this operation affectingproductivity adversely.

Thus, according to a more preferred mode of the present invention,attention is focused on the sole plate of the door opening of a cokeoven, and by blowing air or oxygen from the sole plate of the dooropening into a gas passage formed in the oven door, oxygen-containinggas such as air or oxygen can be easily blow from the outside into thegas passage formed in the oven door, without being affected bydetachment or attachment of the oven door.

Namely, according to another aspect, the present invention is acarbonizing promoting method for a coke oven door region and an ovendoor structure therefor in which coke oven gas which is generated duringcarbonization of coal in a coke oven is introduced into a gas passageformed on the inner side of an oven door, air or oxygen is blown duringcarbonization and the coke gas is combusted and the carbonization ofcoal in the door region is promoted, characterized in that an oxygencontaining gas is blown into the gas passage from a location in the doorregion facing the lower end of the oven door, such as the sole plate ofthe coke oven door opening.

According to the present invention, a portion of coke oven gas iscombusted in the gas passage by an oxygen containing gas, such as air oroxygen, which is blown from a blowing nozzle, and it is advantageous tokeep the temperature in the gas passage at 600° C. or higher because thecoke oven gas which is generated during carbonization has a tarcomponent, and at a temperature of 600° C. or below, a portion thereofcondenses and there is a fear of hollow portions of the carbonizingchamber or the gas passage becoming blocked. In order to prevent theformation of black smoke and dust at the time of coke discharge due toinadequate carbonization and to guarantee shrinkage of the coke, thetemperature of the coke side door region in the last stages ofcarbonization is preferably at least 700° C. There is no particularupper limit on the temperature of the gas passage as long as such atemperature can be guaranteed, but it can be determined taking intoconsideration the extent of worsening of the sealing ability due tothermal strains of the main metal frame of the oven door whichaccompanies an increase in temperature.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic explanatory view of a carbonizing chamber of acoke oven;

FIG. 2 is a schematic horizontal cross-sectional view showing an exampleof a conventional oven door structure;

FIG. 3 is a schematic horizontal cross-sectional view showing anotherexample of a conventional oven door structure;

FIG. 4 is a schematic horizontal cross-sectional view of an embodimentof this invention;

FIG. 5 is a view taken along line a--a of FIG. 4;

FIG. 6 is a schematic view of one embodiment of a fitted joint of heatresistant members according to this invention; and

FIG. 7 is a schematic explanatory view showing the installation of anair or gas supply nozzle of the sole plate in another embodiment of thepresent invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Details of the present invention will be explained based on FIG. 4through FIG. 6.

FIG. 4 is a schematic horizontal cross-sectional view of an oven doorused in the method of the present invention, FIG. 5 is a view takenalong line a--a of FIG. 4, and FIG. 6 is a schematic view showing thefitting of a heat resistant member used in the method of the presentinvention. An oven door is provided on the door opening on both thepusher side and the coke side, but the following explanation will notdistinguish between the two doors and will refer simply to an oven door.

As is clear from the illustrated example, the oven door 40 is formedfrom main metal frame 42, a heat insulating material 43, a heatresistant member 45 having a cylindrical or concave cross-sectionalshape and which forms a gas passage 44 in its interior, a connectingmember 46 which intimately fixes the heat resistant member 45 to theheat insulating material 43, and a blowing nozzle 47 which blows airinto the gas passage 44.

The heat resistant member 45 is preferably formed of a castable mixedwith reinforcing fibers such as all types of steel fibers, carbonfibers, or ceramic fibers. In order to prevent the ingress of chargedcoal into the gas passage 44, as shown in FIGS. 5 and 6, the upper endsurface is made an outwardly facing sloped surface 48, the lower end ismade an inwardly facing sloped surface 49, a plurality of heat resistantmembers 45 are aligned in the vertical direction and the slopingsurfaces on the upper and lower face each other across a gap 50, the gapA between each heat resistant member 45, 45 is preferably made at most50 mm, the overlapping portion B is preferably made at least 50 mm, andthe heat resistant members are preferably secured to the heat insulatingmaterial 43 by a connecting member 46.

The gap A between the heat resistant members 45, 45 is made at most 50mm because it was confirmed by tests that if the gap is greater thanthis amount, ingress of charged coal into the gas passage 44 cannot beadequately prevented. In addition, from the standpoint of maintaininggas flow between the gas passage 44 and the carbonizing chamber, the gapA between the heat resistant members 45 is preferably made as wide aspossible below the upper limit of 50 mm. The reason why the overlap Bbetween the heat resistant members 45, 45 is made at least 50 mm arerequired to prevent ingress of charged coal into the gas passage 44.

The separation between the oven wall 51 of the carbonizing chamber 12and the heat resistant members 45 can be set to the same value of 10-20mm as generally used in the conventional oven door of FIG. 2.

According to a more preferred mode of the present invention, the heatresistant member 45 has a side portion thickness D which is greater thanthe front portion thickness C. The heat which is obtained by combustionof the coke oven gas in the gas passage 44 is, therefore, effectivelytransmitted to the coal layer 24 within the carbonizing chamber, thetransmission of heat to the oven wall 51 is reduced, and the loss ofheat from the door frame 52 is suppressed. The ratio of the side portionthickness D to the front portion thickness C of the heat resistantmember 45 varies depending upon the heat insulating capability of theheat insulating member 45, but in general if D/C is at least 2, the lossof heat to the door frame 52 can be minimized. In order to reduce theheat capacity, a small front portion thickness C is preferable, and itcan be suitably selected from a range in which a prescribed degree ofstrength is obtained.

The oxygen-containing gas blowing nozzles 47 for blowing air, oxygen,etc. into the gas passage 44 (hereunder sometimes referred to simply asair blowing nozzles) are constructed so as to blow an oxygen-containinggas such as air or oxygen and ignite and combust coke oven gas whichflows from the spaces 50 between the heat resistant members 45, 45 intothe gas passage 44. An unillustrated ignition apparatus such as a sparkplug is mounted on the ends of the air blowing nozzles 47.

Due to the above-described construction, coke oven gas which flows intothe gas passage 44 through the gaps 50 between the outwardly facingsloped surfaces 48 and the inwardly facing sloped surfaces 49 of theheat resistant members 45, 45 is combusted by the oxygen gas blown intothe gas passage 44 by the air blowing nozzles 47, and as the gas isbeing carried to the upper space by the chimney effect of the gaspassage 44, the heat of combustion is transmitted to the charged coal 24within the carbonizing chamber through the front surfaces of the heatresistant members 45, the charged coal 24 contacting the front surfacesof the heat resistant members 45 is heated, and carbonization ispromoted.

By making the side portion thickness D greater than the front portionthickness C of the heat resistant members 45, the heat which is obtainedby combustion of the coke oven gas which penetrates the gas passage 44is effectively transmitted to the charged coal 24 within the carbonizingchamber, heat transmission to the oven wall 51 is decreased, and loss ofheat through the door frame 52 can be suppressed.

FIG. 7 shows another variation of the present invention. According tothis variation, an oxygen-containing gas inlet is provided in the doorregion facing the lower end of the oven door. Namely, as shown in thefigure, air piping 72 is provided on the operating deck 70 at the lowerportion of the door region of a carbonizing chamber 12 along a row ofcoke ovens, a shutoff valve 76 is provided on a branch pipe 74 from theair piping 72, and the end of the branch pipe 74 passes through the soleplate 78 and forms a nozzle opening 80 which opens into the gas passage44. Accordingly, if the valve 76 is opened, air passing through the soleplate 78 can be blown into the gas passage 44 of the oven door 40through the nozzle opening 80, and coke oven gas which flows into thegas passage 44 through the gaps between the heat resistant members 45,45 can be ignited and combusted. In this case as well, an ignitionapparatus such as an unillustrated spark plug is provided on the tip ofthe nozzle 80.

In this manner, the supply of air (oxygen) to the gas passage 44 in theoven door 40 is carried out via the valve 76 through the branch pipe 74which branches from the air piping 72 which is installed on theoperating deck 70 along the row of coke ovens. The sole plate 78 isintegrated with the carbonizing chamber 12, so the blowing ofoxygen-containing gas can be carried out without being troubled by thedetaching and attaching of the oven door 40.

According to the present invention, a heat resistant member which isexposed to high temperature and is pressed by charged coal has goodresistance to thermal deformation and corrosion and has excellentdurability, and in addition, due to the use of a castable, it hasincreased durability and economy.

By making the side portion thickness of the heat resistant membergreater than the front portion thickness, the heat which results fromcombustion of coke oven gas in the gas passage can be effectivelytransmitted to the coal charged inside the carbonizing chamber, thetransmission of heat to the oven wall is reduced, and heat loss throughthe door frame can be suppressed.

Furthermore, if the connecting member to the main metal frame isembedded in the castable of the heat resistant material, it is notexposed to high temperature combustion gas, and its durability can bemaintained. In addition, the heat resistant members which are inintimate contact with the heat insulating material form a box-shaped gaspassage, and the sloping surfaces at the upper and lower ends of theheat resistant members are installed so as to oppose each other across agap, so ingress of coal into the gas passage from a carbonizing chamberin which the coal having been charged by gravity can be prevented, andthe flow of coke oven gas from the carbonizing chamber into the gaspassage can be guaranteed. As a result, stable combustion of coke ovengas by air or oxygen is possible.

In the above-described mode of the present invention, by blowingoxygen-containing gas such as air or oxygen into the gas passage from alocation opposing the bottom of the oven door of the coke oven doorregion, such as from the sole plate, it is not necessary to remove andinstall the piping each time the oven door is detached or installed, andwhen the oven door is detached or attached, special labor or theinstallation of special equipment is not necessary, so coke gas can becombusted in the gas passage formed in the oven door as desired, thereis no effect on the coke discharged operation of the coke oven, theobtained heat is effectively transmitted to the coal within thecarbonizing chamber, heat transmission to the oven wall is reduced, heatloss through the door frame can be suppressed, and promotion ofcarbonization in the coke oven door regions can be achieved.

EXAMPLES! Example 1

In a coke oven measuring 7,125 mm high, 460 mm wide, and 16,500 mm long,under controlled humidity operating conditions with an operating timeefficiency of 95%, an average combustion chamber temperature of 1038°C., a water content of 6.1% in the charged coal, and an average bulkdensity of 780 kg/m³ for the charged coal, the oven door for the doorregion on the pusher side was varied among that shown in FIG. 4 (twoexamples of the present invention), that shown in FIG. 2 (ComparativeExample 1), and that shown in FIG. 3 (Comparative Example 2). Thetemperature rise of the coke, the time required for coking, thegeneration of black smoke from the oven door, and ingress of chargedcoal into the gas passage were investigated.

The dimensions and materials of the various oven doors are shown inTable 1.

In order to investigate the increase of temperature of coke in the doorregion, a temperature sensing hole was formed in the center of each ovendoor at a location 3 meters above the oven bottom, and the temperatureof the end surface of the charged coal layer or coke layer whichcontacted the oven door and the temperature of the gas passage weremeasured.

In the case of FIG. 4 (2 examples of the present invention) and FIG. 3(Comparative Example 2), an air blowing nozzle for combustion wasinstalled in a location 30 cm from the bottom of the oven door, anignition apparatus generating an electric spark was provided on the endof the nozzle, a portion of the coke oven gas which was generated duringcarbonization was combusted beginning 2 hours after charging of coal,and the temperature in the gas passage was maintained at 800° C.

The experimental results are shown in Table 2.

                                      TABLE 1                                     __________________________________________________________________________               Overall                                                                            Heat Insulating Material                                                                 Gas Passage                                                                         Heat Resistant Members                                  Thickness                                                                          Thickness  Width Thickness                                               (mm) (mm)  Material                                                                           (mm)  (mm)  Material                               __________________________________________________________________________    Example 1  350  150   Ceramic                                                                            130   Front (C) 70                                                                        Castable containing                    (Present Invention)   Fibers     Side (D) 150                                                                        stainless steel wire                   Example 2  350  150   Ceramic                                                                            130   Front (C) 70                                                                        Castable containing                    (Present Invention)   Fibers     Side (D) 70                                                                         stainless steel wire                   Comparative Example 1                                                                    350  350   Refractory                                                                         --    --    --                                     (Conventional Oven    Brick                                                   Door)                                                                         Comparative Example 2                                                                    350  150   Ceramic                                                                            190   10    Stainless Steel                                              Fibers                                                  __________________________________________________________________________

                                      TABLE 2                                     __________________________________________________________________________               Coking                                                                            Temperature of End                                                                     Door Frame                                                                          Bake Stay  Ingress of                                      Time                                                                              Surface of Coke                                                                        Temperature                                                                         Temperature                                                                              Coal                                            (hr)                                                                              (°C.)                                                                           (°C.)                                                                        (°C.)                                                                        Gas Leaks                                                                          (Kg)                                 __________________________________________________________________________    Example 1  20.6                                                                              814      253   131   None None                                 (Present Invention)                                                           Example 2  20.9                                                                              799      291   155   None None                                 (Present Invention)                                                           Comparative Example 1                                                                    22.8                                                                              561      216   114   Leaks                                                                              None                                 (Conventional Oven                  Occurred                                  Door)                                                                         Comparative Example 2                                                                    21.3                                                                              783      382   231   None 62                                   __________________________________________________________________________

As shown in Table 2, during coke discharge, the temperature of the endsurface of the coke in the door region which contacted the oven door was561° C. for the conventional oven door of Comparative Example 1, and itcannot be said that an adequate temperature for coking was reached. Thiswas also confirmed by visual observation at the time of coke discharge.During charging under controlled humidity conditions, the pressure inthe door region increases, and as a result, with the conventional ovendoor of Comparative Example 1, gas leaks were observed.

In contrast, in Examples 1 and 2 of the present invention, it wasconfirmed that the temperature of the coke end surface reached 814° C.and 799° C., which are adequate temperatures for the formation of coke.Although the temperatures of the door frame and the back stay bothslightly increased, they did not reach temperatures within a range whichcould cause a variation in operational results. In addition, no gasleaks were observed at all, and ingress of coal into the gas passage wasalso not observed at all.

On the other hand, in Comparative Example 2, although the temperature ofthe end surface of the coke increased compared to that of theconventional oven door of Comparative Example 1, it did not reach thelevel of Examples 1 and 2 of the present invention. In addition, thedoor frame temperature and the back stay temperature were both muchhigher than for a conventional oven door. Although no gas leaks wereobserved at all, there was very much ingress of coal into the gaspassage, and it was of an amount that could not be permitted duringnormal operation.

Due to the fact that the rise in the temperature of the door region wasfast and the delay in carbonizing was overcome in the examples of thepresent invention, the time required for coking was 20.6 hours forExample 1 and was 20.9 hours for Example 2 of the present invention,both of which are large improvements. It was 2.2 hours less than for theconventional method of Comparative Example 1 and was 0.7 hours less thanfor Comparative Example 2, confirming that the method of the presentinvention provides significant effects.

Example 2

In this example, a nozzle for blowing oxygen-containing gas wasinstalled on the sole plate of the door region on the pusher side, asshown in FIG. 7.

Namely, in a coke oven measuring 7,125 mm high, 460 mm wide, and 16,500mm long, under controlled humidity operating conditions with anoperating time efficiency of 100%, an average combustion chambertemperature of 1053° C., a water content of 6% in the charge coal, andan average bulk density of 780 kg/m³ for the charged coal, as shown inFIG. 7, an oven door according to this invention equipped with a nozzlefor blowing an oxygen-containing gas on the sole plate or a conventionaloven door of the type used in Example 1 and shown in FIG. 2 wereinstalled, and the rise in temperature of the coke and coking conditionswere investigated in a location 3.5 m above the oven bottom and 100 mmfrom the side of the oven door.

When using an oven door according to the present invention, air wasblown from the sole plate of the coke oven door region from 10 hoursafter the start of carbonizing until 20 hours after the start ofcarbonizing, coke oven gas was combusted in the gas passage, and thetemperature in the gas passage was maintained at 830° C.

The results are shown in Table 3.

                                      TABLE 3                                     __________________________________________________________________________              Coking                                                                            Coke Temperature 100 mm                                                                   Door Frame                                                                          Back Stay                                               Time                                                                              from the side of oven door                                                                Temperature                                                                         Temperature                                             (hr)                                                                              (°C.)                                                                              (°C.)                                                                        (°C.)                                  __________________________________________________________________________    Present Invention                                                                       19.4                                                                              782         218   110                                           Comparative Example                                                                     21.6                                                                              555         220   119                                           __________________________________________________________________________

As shown in Table 3, the coke temperature at a location 100 mm from theside of the oven door at the time of coke discharge was 555° C. andinadequate for carbonization for the conventional oven door of thecomparative example. It cannot be said that an adequate temperature forcoke formation was reached, and the generation of black smoke wasvisually observed at the time of coke discharge. In contrast, in theexample of the present invention, the temperature of the coke endsurface reached 782° C. which is sufficient for coke formation, no blacksmoke was ascertained during visual observation at the time of cokedischarge, and due to the increased thermal insulation, the temperaturesof the door frame and the back stay were lower than for the conventionaloven door.

Due to the fact that the rise in the temperature in the door region wasfast and the delay in carbonizing was overcome in the examples of thepresent invention, the time required for coking was 19.4 hours for theexample of the present invention and was greatly improved compared tothe 21.6 hours for the conventional oven door.

As described above, according to the method of the present invention inwhich air or oxygen is blown into a gas passage formed by heat resistantmembers made from a castable in which reinforcing fibers are mixed andwhich are fit together with an air gap therebetween and which areinstalled on the main metal frame of an oven door, ingress of chargedcoal into the gas passage can be prevented and the flow of gas from thecarbonizing chamber into the gas passage can be guaranteed, and bystably combusting using air or oxygen a portion of the gas which isgenerated during carbonizing, the fear of heat loss from the oven bodyaccompanying a rise in temperature of the door frame is done away with,effective heating of coal in the door region becomes possible, anduniformizing of carbonization, an increase in productivity, a decreasein the amount of heat required for carbonization, and an improvement inthe quality of coke can be achieved, and the present invention makes alarge contribution to an increase in the efficiency of a coke oven andstabilization of coke quality.

In addition, the pressure on the door region during charging of coal canbe decreased, and the present invention also exhibits the excellenteffects from the standpoint of improving the environment in that gasleaks and the generation of black smoke can be prevented.

We claim:
 1. A method for promoting carbonization in a door region of acoke oven comprising the steps of providing a gas passage formed on aninner side of the coke oven door, introducing into said gas passage acombustible gas which is generated during carbonization of coal in thecoke oven and introducing an oxygen containing gas into said gaspassage, preventing ingress of charged coal into the gas passage andcombusting the combustible gas in the gas passage, whereby carbonizationof coal in the door region is promoted.
 2. A method for promotingcarbonization in a door region of a coke oven, comprising the steps ofproviding a plurality of heat resistant members having a substantiallyconcave cross section wherein said members fit together with gapsbetween sloping surfaces on respective upper and lower ends of adjacentheat resistant members, providing a heat insulating material on a mainmetal frame of an oven door to form a closed space with the gapsremaining, introducing an oxygen containing gas into a gas passagedefined by the closed space formed by the heat resisting members,introducing into said gas passage through said gaps a combustible gaswhich is generated during carbonization of coal in the coke oven andcombusting said combustible gas and oxygen in the gas passage.
 3. Amethod for promoting carbonization in a door region of a coke oven,comprising the steps of providing a heat insulating material on theinner side of the main metal frame of an oven door of a coke oven,forming a gas passage extending in the vertical direction using aplurality of heat resistant members having a substantially concave crosssection wherein said heat resistant members each have a side portionthickness which is greater than a front portion thickness, whereinbetween said members and joints the heat insulating material of the ovendoor are sealed to prevent an ingress of charged coal into the gaspassage, introducing an oxygen containing gas into the gas passage, andcombusting a combustible gas which is generated during carbonization ofcoal in the coke oven with said oxygen in the gas passage whereby agreater amount of heat generated in said combusting step passes throughthe front portions of said heat resistant members than through said sideportions.
 4. A method for promoting carbonization in a door region of acoke oven, comprising the steps of providing a gas passage formed on theinner side of an oven door of the coke oven, introducing a combustiblegas which is generated during carbonization of coal in the coke oveninto the gas passage and introducing an oxygen containing gas into thegas passage through a main body of the oven door, preventing ingress ofcharged coal into the gas passage, combusting the combustible gas withinthe gas passage, whereby carbonization of coal in the door region ispromoted.
 5. A coke oven door comprising a plurality of members forforming a gas passage on the inner side of the oven door body of a cokeoven, said members having inlets to permit the ingress of a combustiblegas from the coke oven into the gas passage, said inlets being slopedupward from an outside to an inside of the gas passage, and inlet meansfor introducing an oxygen containing gas into said gas passage, wherebycombustion of said combustible gas occurs in said gas passage.
 6. Thecoke oven door according to claim 5 wherein the members for forming thegas passage have slit shaped inlets for the ingress of a combustiblegas.
 7. The coke oven door according to claim 5 wherein the members forforming the gas passage have a side portion thickness which is at least2 times a thickness of a front portion which adjoins a charged coallayer whereby a greater amount of heat generated by the combustion ofsaid combustible gas passes through the front portion of the gas passageforming members than through the side portion.
 8. The coke oven dooraccording to claim 5 wherein the members for forming the gas passagehave an upper end surface and a lower end surface, each end surfaceformed with an upward slope extending from an outside to an insidesurface of said member, said members having a cylindrical or nearlyconcave cross section, and wherein the members are vertically alignedand spaced apart to define a gap between each end surface which servesas the inlets for ingress of said combustible gas into the gas passage.9. The coke oven door according to claim 5 wherein the inlet means forintroducing the oxygen containing gas is disposed in a door regionfacing a bottom end of the oven door.
 10. The coke oven door accordingto claim 9 wherein the inlet for oxygen containing gas is provided on asole plate of the door region.